Author
Topic: BlowBy (Read 1030 times)

So, as noted in my oil change from hell thread, when I ran the engine with the dipstick removed (fresh fill to measured capacity) I got enough of a pulsing wind out of the dipstick hole to put a nice oil mist over everything. Is this normal on these engines with their small crankcase volume or do I have a problem? It really didn't smell strong like blowby, I am hoping it is just compressor effect from piston displacement..C'mon, one of you gullible Norge owners go out with a rag and pull the dipstick and start the engine and tell me what happens to you.. 2008 Norge with about 40Kmiles on the clock.

Vasco DG

Crankcase volume varies by about 2/3rds of swept volume between its maximum, when the crankpin is at 12 O'clock and its minimum when the crankpin is at 6 O'clock. Hence the pumping action. On something like a straight four or other multis with crank pins at 180* crankcase volume remains almost constant. On a boxer twin it varies by the full swept volume every revolution.